My name is Robert,I have a 1973 Chevrolet Cheyenne long bed,5.7 liter,350 turbo transmission.im going to purchase a new wire harness and I don't know witch harness I need to buy.i went to a website,entered my trucks information and the wire harnesses are categorized by circuits and I don't know how many circuits I need to get.any help will be very much appreciated,thank you fellow C10er's